A rotating member is typically supported relative to a fixed member using some form of bearing. Often, the beating is a gas or liquid film bearing. However, when run in a vacuum environment, lubricants cannot be used. Unlubricated rolling element bearings tend to be noisy. Magnetic beatings have found use in such applications.
A typical magnetic bearing system for a shaft employs radial beatings and thrust bearings. A radial bearing usually includes four magnets arranged in actuator pairs to respond to loads in a radial axis. A double acting thrust beating responds to loads in a longitudinal axis. Due to inductance, a large beating sized for high load capacity becomes too sluggish to respond to high frequency load variations. While smaller bearings could be used instead to provide faster response, such smaller bearings may not be able to handle high loads.
The present invention is directed to solving one or more of the problems discussed above in a novel and simple manner.